Size controlling mechanism



7 June 17, 1941. M H, ARMS SIZE CONTROLLING MECHANISM Filed Feb. 10, 1939 9 Sheets-Sheet 1 June 17, 1941. M. H. ARMS 2,245,894

SIZE CONTROLLING MECHANISM Filed Feb. 10, 1939 9 Sheets-Sheet 2 June 17, 1941. M. H. ARMS SIZE CONTROLLING MECHANISM 9 Shets-Sheet 3 Filed Feb. 10, 1939 9 June 17, 1941. M. H; ARMS SIZE CONTROLLING MECHANISM Filed Feb. 10, 1939 9 Sheets-Sheet 4 June 17, 19 41. M. H. ARMS SIZE CONTROLLING MECHANISM 9 Sheets-Sheet 5 Filed Feb.' 10, 1939 iv M M Qa June 17, 1.941. ARMS 2,245,894

SIZE CONTROLLING MECHANISM June 17, 1941. ARMS 2,245,894

SYIZE CONTROLLING MECHANISM I Filed Feb. 10, 1939 9 Sheets-Sheet 8 jzi/wfir June 17, 1941. I ARMS 2,245,894

SIZE CONTROLLING MECHANISM Filed Feb. 10, 1939 9 Shets-Sheet 9 4 45 "41/ i /l 4Z7 I 4M7 v Ll AGE I I REGLIILIATOR J/r 40 FM g 47L; w 221E z M J 4/] M r E 47/ I Z6 K /WZ'ZIZ Patented June 17, 1941 SIZE CONTROLLING MECHANISM Merton H. Arms, Springfield, Vt., assignor to Bryant Chucking Grinder Company, Spring- "fleld, Vt., a corporation of Vermont Application February 10, 1939, Serial No. 255,604

28 Claim.

' matically gaging each finished piece, the result of the gaging determining the feed setting of the tool for operation on a subsequent piece.

While the invention broadly is applicable to a great variety of machines and machining operations, certain embodiments shown herein by way of illustration and not of limitation, employ grinding as the operation controlled, and more specifically,'internal grinding.

Such embodiments are illustrated in the accompanying drawings in which Figure 1 is a front elevation of a single spindle grinding machine embodying this invention.

Figure 2 is a detail section to a much larger scale on line 2-2 of Figure 1 and showing the gaging mechanism.

Figure 3 is a detail section on line 33 of Figure 2.

Figure 4 is a fragmentary view partly in section of a portion of the tool feeding mechanism shown in elevation and to a smaller scale on Figure 1.

Figure 5 is a detail section to a'larger scale on line 5--5 of Figure 1.

Figure 6 is a detail section on line 6-6 of Figure 4.

Figures 7 and 8 are fragmentary elevations of portions of the mechanism shown in Figure 4, but in different positions.

Figure 9 is an electrical diagram of the feed control mechanism.

Figure 10 is a front elevation of a multiple spindle grinding machine embodying the invention and with automatic gaging.

Figures 11 and 12 are detail sections on the correspondingly numbered. section lines of Figure 10.

Figure 13 is a detail section on line l3l3 of Figure 12.

' Figure 14 is a detail view partly in elevation and partly in section of the mechanism shown in Figures 12 and 13 looking toward the left.

Figure 15 is a detail section on line |5-l5 of Figure 14.

Figure 16 is a detail section on line l6l6 of Figure 15.

Figure 17 is a detail section on line ll-I'l of Figure 18 and through the automatic gaging and" work feeding mechanism.

Figure 18 is a detail section on line l8--IB of Figure 17.

Figure 19 is a detail section to a larger scale of the gaging head shown in elevation in Figure 17 and with the finished work in gaging position.

Figure 20 is a view similar to a portion of Figure -19, but showing the workpiece preparatory to being ground and as it is being presented to the work spindle.

Figure 21 is a central longitudinal sectional view of the machine shown in Figure 10.

Figures 22 and 23 are detail sections on the correspondingly numbered section lines of Figure 21.

Figure 24 is a detail section on line 24-24 of Figure 23.

Figure 25 is a view similar to Figure 4 but showing the part in indexing position.

Figure 26 is an electrical diagram of the gaging and sizing control mechanism.

Referring first to the construction shown in Figures 1 to 9, the invention is shown as applied to an internal grinding machine of the general type shown in the Bryant Patent No. 1,765,787 granted June 24, 1930, to which patent reference may be had for the details of operation of the machine. For present purposes it is only sufficient to pointvout that the work pieces are held individually in a rotary work holder I and that the grinding wheel (not shown) iscarried by a rotary shaft 2 slidably journaled in an arm 3 which is mounted for rocking motion coaxial with a grinding wheel drive shaft 4. The drive shaft 4 carries a pulley 5 about which a belt 6 passes and which also engages around a small-pulley on the outer end of the grinding wheel shaft 2. The feed motion of the grinding'wheel with reference to the work is produced by swinging the arm 3 about its pivotal axis, this being accomtion of the sleeve 8, produces axial motion of the screw and a consequent feed and retracting motion to the grinding wheel, depending on the direction of rotation of the sleeve 8. At its outer end this sleeve 8 has keyed thereto a sleeve III which has journaled thereon a feed wheel il retained in position between a flange 12 on the inner end of the sleeve I and a nut I3 threaded on its outer end. This wheel II is provided with one or more handles I I by which it may be turned and it has fixed therein a stub shaft II! which has Journaled thereon a gear collar It. This collar It has two integral gears I1 and I 8 thereon, the teeth of the gear I1 meshing with teeth out in the fiange I2 of the sleeve l0, while the teeth of the gear I8 engage teeth in a gear portion I9 of a sleeve 20 joumaled on the bushing 9. The

sleeve 20 is provided with a worm gear portion 2i with which meshes a worm 22 keyed to a sleeve 23 (see Figures 4 and which in turn is rotatable on a shaft 28 and in bearings 23a. It will be evident, therefore, that by rotation of the sleeve 23, the sleeve I9 will be'turned and through its geared connection through the sleeve I8 it 'will rotate the sleeve I0 and the nut 0, even and with it the nut 0, and as the feed wheel II may be efiected in the same manner as the rotation of the wheel 90 in the patented construction, no further discussion thereof will be made herein. A feed motion is also produced by the rotation of the sleeve I9.

As shown best in Figure 4, the shaft 20 has splined thereon an axially movable sleeve 30, one end of which is formed as one member of a'clutch at 3|, while the other end portion is formed with an integral gear 32, which by axial motion of the sleeve 30 may be moved into any one of three positions shown in Figures 4, 'I and 8, respectively. In Figure 4 the gear 32 is in mesh with a gear 35 journaled on a stub shaft 38. In Figure 7 the gear 32 is shown in mesh with a gear 31,

also journaled on the stub shaft 38, while in Figure 8 the gear 32 is positioned between the gears 35 and 31 and in mesh with neither, this being a neutral position of the sleeve 30. It will likewise be noted that in the position of Figure 4, where the gear 32 is in mesh with the sear 85, the clutch at 3| is closed, there being a mating clutch element 39 carried at the left hand end of the sleeve 23 to which the worm 22 is fixed. In both of the other axial positions of the sleeve 30 shown in Figures '7 and 8, the clutch at SI is in unclutched condition so that the worm 22 is rotarily disconnected from the sleeve 3| and hence receives no motion from rotation of this sleeve 30. The two gears 35 and 31 are driven in opposite directions. Each is provided with an integral belt pulley such as 80 and 4| and these pulleys have engaged therewith the belts 62 and 43, the belt 83 being shown as crossed and both passing about an elongated driving pulley 44 (see Figure 1), fixed to the main power shaft of the machine and which carries the main drive pulley 45. The sleeve 30 is shifted from one to another of its three positions by means of a shift lever 50 fulcrumed at 5| to a portion of the machine frame and carrying at its upper end cam rollers 52 (Figures 4 and 6) riding in a cam groove 53 in the sleeve 30. The lower end of the lever 50 has secured thereto one end of a spring 54, the other end of which is secured to a fixed part of the machine frame as at 55, this spring biasing the lever 50 to the position shown in Figure 7 with the lever contacting a fixed stop 00, the gear 32 being then in mesh with the gear 31 and the clutch at 3| open.

Two means are effective to swing the lever 50 in opposition to the tension of the spring 54. One of these means comprises a magnetic plunger pivoted to the lever 50 at BI and extending into a solenoid 82. The other means comprises a bumper bar 65 mounted for axial movement in the guide lugs 66 and 81 and which is provided with a rounded head 88 which may impinge on the lever 50 below its fulcrum 5|. This bumper bar 65 may be struck at its opposite end by an abutment 10 on a slide 1| (Figure 4). this slide is guided on a pin 12 fixed to the guide lug 61 and has threaded engagement with a threaded end portion 14 of the shaft 24. Thus as the shaft 28 is driven in one or the other direction by rotation of the sleeve 30, depending with which of the gears 35 and 31 the gear 32 is then in mesh, the member H is traversed and when moved to the left, as shown in Figure 4, it may contact with and move the bumper bar 65 to the left. In the position shown in Figure 4, however, the abutment 'ID has been retracted out of contact with the bumper bar 65. It should be noted, however, that the worm 22 which drives the feed shaft 2i is rotated in one direction only since it is only when the sleeve 30 is in its right hand position with the gear 32 in mesh with the gear 35 that the clutch at 3| is closed. This is the feed direction of rotation of the worm gear 2| and therefore compensates for wear in truing of the wheel in efiecting a feed provided,the work gaged, which controls the extent of, this feed, is insufiiciently ground away. The slide 1| carries insulated therefrom a contact slider 15 which rides across a resistance coil 16, thus to cut in or out resistance of this coil depending on the direction of motion thereacross. The variable resistance I6 (Figure 9) constitutes a corrective follow-up portion of an electrical system including the gage by the response of which the feed control, through the mechanism just described, is roduced.

The gage itself is shown in detail in Figures 2 and 3. Referring to these figures, it will be seen that the gage is a plug gage having the tapered plug I00 over which the work piece "II to be gaged may be placed, the extent to which the work piece may descend toward the larger end of the plug being a measure of the size of the hole therein. Through one side of this plug I00 there is formed a slot I02 within which a slider I03 may ride. This slider is mounted on a headed post I00 secured as by threading its lower end at I05 into a base flange I 06 of the gage. This slide I03 is normally lifted into contact with the head I01 of the post I 04 as by means of a li ht coil spring I08 which surrounds the post I04. This spring is too light to counterbalance the wei ht of a work piece Ifll, so that as soon as the work piece is laced over the gaging plug I00, the slider I03 descends, as to the dotted line position shown in Figure 2, as far as the size of the hole in the work piece permits. This slide I03 is provided with an electrical contact finger H0 which, when the slide I03 is in fully raised H is in electrical connection through the slide I03, the post I04 and the spring I08 with a terminal II6. When the slide I03 is in its upper limit of motion, it is also in electrical connection through a contact II1 with a terminal II8, butwhen the slide I03 is depressed. as by the placing of a work piece over the gage plug, the contact between the member H1 and the terminal H6 is broken, and a contact is made between the element Ill and the long spring contact I20 leading to the terminal I2I.

The wiring diagram for the gaging mechanism is illustrated in Figure 9. The resistance coil III of the test gage is arranged in bridge formation with the resistance I26 of a standard gage plug with a work piece S of desired standard size thereon, a variable resistance I26, and the resistance 16 across which the slider 16 traverses as previously described. At I30 is a microammeter which is adapted to register the balance or lack of balance between the various resistances in the bridge circuit, and when out of balance in one direction to make contact at I3I with a lead I32. This lead I32 is connected up with the slide II 0 in the test gage and when there is no work piece thereon makes contact with the terminal II8 as previously described. This terminal leads to one side of a source of low potential through the lead I33. The other side I34 of this low potential supply leads to one corner of the bridge at a and through the line I35 to the coil I36 of a relay, which, when energized, closes the two switches I31 and I38. The opposite side of the relay coil I36 is connected to the line I32. When the test gage has no work piece thereon, the contact between the slide I03 and the terminal I I8 is made, completing a connection from the low potential line I33 through the line I32,

the relay coil I36, back to the line I34. This energizes the relay and closes the switches I31 and I38. The closure of the switch I38 also completes a low voltage circuit from the line I33 through the switch I38. the line I33. the ammeter contact I3I and line I32, the coil I36 and the line I35 to the line I36, so that the switch I38 is held closed even though the contact at H8 is broken.

When the finished piece to be aged is placed on the plug gage, thus breaking the contact at H8 and making a contact with the element I20, the switch I31 being then closed. a connection is made from the line I33 through the contact 20 through the relay coil I40 back throu h the switch I31 and the line Hi, the line I35. and back to the opposite side of the low volta e source. This closes the switches I45 and I46 from the high voltage source through the solenoid 62. This acts to pull the core 60 to the left, thus rocking the lever 50 and closing the clutch at 3I and bringin the gears 32 and 35 into mesh as shown in Figure 4. This causes the sleeve 23 as well as the shaft 24 to be rotated in one direction, the rotation of the sleeve 23 acting to turn the feed wheel in feeding directo balance the bridge circuit and proportional to the departure of such measured dimension from the exact dimension desired, and as soon as this is accomplished, the contact at I3I is broken which therefore deenergizes the relay coil I36 which cannot at that time receive energy through the contact II8. This causes the switches I31 and I38 to open, the opening of the switch I31 immediately deenergizing the relay coil I40, causing the deenergization of the solenoid 62. This permits the spring 54 to throw the lower end of the lever 50 to its extreme right hand position, this throwing the sleeve 30 to the left and bringing the gear 32 into driving relation to the gear 31. This gear 32 is thus rotated in the reverse direction, but as the clutch 3| is now open, the feed wheel 2I is not moved in either direction, but the shaft 24 is now driven in a reverse direction. Its threaded connection with the slide 1i, then causes this slide to return toward the left until the abutment." strikes the bumper bar and moves this bumper bar to the left until it reaches the position in Figure 8, where the gear 32 has been moved to its neutral position. This condition persists as long as the work piece being gaged remains on the test gage plug I00, the presence of this work piece preventing the closing of the contact at II8 with the slide I03 which is necessary in order-to effect energization of the relay coil I36 and the closing of the switches I31 and I38. It will thus be seen that each time a finished work piece is placed over the test gage and the bridge circuit is out of balance, an additional feed motion of the wheel toward the work accompanied by a corrective follow-up changing the electrical condition in a direction to bring the parts back to balanced condition is produced, this feed stopping, however, the moment that bridge balance is reached at which time a corrective feed for the next grinding operation has been made, its extent depending on the amount of departure from correct size of the previously ground piece as determined by the a test gage. The reverse rotation of the shaft 24 brings the corrective follow-up back to starting position out of control by the gage, in condition for a subsequent gaging operation on the last sized piece of work.

In Figures 10 to 21, inclusive, there is illustrated an internal grinding machine of the multispindle type in which the work is automatically fed to the work spindles and when completed is removed therefrom, the work being automatically gaged while it remains on the work holder after the grinding operation and in response to which gaging the feed of the final wheel is adjusted preparatory to operating on the next work piece presented thereto.

The particular machine shown in this application and illustrated in these figures is not claimed herein per se and' forms subject matter of an application for patent of Johnson et al Serial No. 152,582, filed July 8, 1937, for Multiple spindle machine. This machine comprises abase tion. The rotation of the shaft moves the slide 10 and the slider 15, thus changing the effective value of the resistance 16, in a direction forms an abutment on which may ride shoes 206, each shoe being carried by means, which will later be more fully described, by a grinding unit 201. There are one less grinding units than there are work holders, so that one of the indexing stations shown at A in Figure 18 has no grinding wheel and is a loading and unloading station at which the finished pieces of work are removed from the work holders and the pieces of work to be ground are inserted in position therein for the subsequent grinding operations. Each of the grinding wheel units comprises a casing 208 having a tubular portion 209 journaled in a sleeve 2! in which it is rockably and axially movable. The axial motion is one of traverse to cause the grinding wheel to traverse the work and may be produced by any suitable mechanism, the details of which are not material to this invention. The feed of each of the grinding wheels with relation to the work piece at its respective station is accomplished by movement of its shoe 206 in a manner to determine the angular position of the casing 201 with relation to its supporting sleeve 2l0 but for the purpose of this invention only that grinding wheel which is positioned to produce the finishing cut is of importance, since it is this wheel only which is controlled by the work gage.

' Referring to Figure 12, each shoe 206 is carried by a short shaft 2I6 which has threaded connection at 2!? with a portion of a lever 2i8. The lever 2l8 is fulcrumed at 2l9 on a bar 220 which is axially adjustable, this axial adjustment being produced, as will later appear, in response to the automatic gaging oi the work piece at the loading and unloading station, the grinding of which has just been completed by the grinding wheel of the finishing unit. The opposite end of the lever 2? is provided with a hardened wear piece 22! which engages an eccentric 222 on a shaft 228. This shaft 223 is provided with a pinion 226 which meshes with teeth on a rack bar 225. This rack bar forms a piston rod to which is attached a piston 226 mounted for reciprocation in a fluid pressure cylinder 221. The piston 226 is normally held at its inner limit of motion, as shown, by a coil spring 230 surrounding the rod 225 and reacting between a collar 23l pinned thereto and a sealing member 232 which acts as a packing for the rod 225 adjacent to the piston 226. By introducing fluid pressure back of the piston 226 as through a port 233, the piston may be driven to the right as viewed in Figure 12, moving the rack bar and rotating the eccentric 222 which rocks the lever 2 i 8. This acts to move the wheel head away from the axis of the shaft 20l and produces a feed of the grinding wheel into the work. This is the normal feed action of the grinding wheel and may be the same construction for all the grinding wheel units, the extent of eccentricity of the eccentric 222 determining the amount of the feed for each work piece and being uniform at each actuation of the feed by this portion of the mechanism, the feed and retraction taking place automatically for eachwork piece operated upon'in one complete machine cycle. A cam shaft 235 (see Figure which is driven in time with the machine is provided with suitable cams thereon for controlling hydraulic valves which cause the introduction and discharge of fluid pressure from the various feed cylinders 22'! and various other hydraulic mechanisms, some not material to this invention, which act to determine the cycle of operations of the machine.

Besides the normal feed of each grinding wheel for operation on each of the pieces of work which is submitted in turn to the action of this wheel; there is also provision for compensating for wheel truing and wear. which as before noted, is efiected by axial motion of the bar 220. For present purposes the construction for effecting such compensation for the last or finishing grinding wheel only is described, as it is to this compensation that a further additional feed may be added to an extent depending upon the response of the gaging mechanism when the last previous work piece has been sized and found to require a correction to be made in the succeeding flnishing grinding operation. The rear end of the bar 220 is threaded at 240 (see Figure 12) and in engagement with this portion is an internally threaded sleeve 2 by the rotation of which the bar 220 may be moved axially. This sleeve 2 is provided at one end with a flange 262 between which and a stationary cap member 268 is positioned the ball bearing 540. The cap member 243 is secured to the grinding wheel unit casing as by screws 2%. Thus the sleeve 22! is held against axial motion relative to the truing mechanism casing while it is permitted angular motion. It has keyed thereto a gear 245 with which meshes a pinion 246 (see Figures 14 and 15) carried by a stub shaft 267. Rotatable with the pinion 246 is a gear 208 which meshes in turn with a gear 249 fixed to a shaft 250. Rockably mounted on a bushing 25! in which the shaft 250 is journaled are two arms 252 which project beyond the gear 269 and have pivoted between them on the pin 258, a feed block 254. This feed block is provided with a slot 255 at its outer end within which rides a pin 256 pm. jecting laterally from the outer end of a rock arm 251. This rock arm is secured to one end of a rock shaft 258 journaled in spaced bearings 250 in a portion 260 of the truing device casing. The opposite end of the rock shaft 258 has secured thereto a rock arm 26! carrying a cam roller 262 at its outer end. This cam roller 262 lies in the path of a cam block or lug 263 (see Figures 13, 14 and 15) extending from a ring 264 which is secured to the rear end of the spider 265 rockable on the sleeve 205 on which ride the shoes 206 of the grinding wheel units. This spider 265 which passes lengthwise of the sleeve 205 between the wheel units is movable axially with the shaft 20! and when the shaft 20l is moved axially into its indexing position the block 263 is brought into alinement with the cam roller 262. The spider 265 has an enlarged end portion 266 (Figures 21 and 23) which carries the truing devices 261 for the grinding wheels and during the last fifteen degrees of indexing motion, it is connected for turning movement with the workcarrying spider. The indexing motion is produced by rocking of the indexing arm 268 (Figures 21 and 22-) in the direction of the arrow, as produced by the fluid pressure motor 2680 acting through the rack 268l and 'the pinion 2682. This arm has a follower 2683 which engages su cessively in the slots 2684 of the Geneva wheel 2685 keyed to the shaft 20! and moved into 00- opera'tive relation to the follower when the shaft 20l is moved axially to bring the work holders out of operative relation to the grinding wheels. Actuation of the motor 2680 to oscillate the arm 268 may be produced by a suitable controlling valve (not shown) actuated by a cam on the cam shaft 235. Axial motion of the shaft 20! to indexing position moves the truing device carrying part 266, which also carries a spring-pressed latch member 2686, from the position shown in Figure 24 to the position shown in Figure 25, when the latch member is in position to be struck by an abutment 2681 carried by the work-holding spider 202, after this spider has been indexed all but fifteen degrees of its complete motion, which, with four spindles would be ninety degrees. The turning of the spider 265 during the indexing motion causes the cam 263 to wipe across the cam roller 262, effecting a rocking motion thereof and lifting the arm 254. This causes a feed dog 210 to engage between the teeth of the gear 249 and to step this gear around to an extent determined by the setting of an abutment screw 210a. The setting of a, pair of adjusting screws 21! and 212 determine the limits of rocking motion of the block 254. The arms 252 are shown as provided with counterbalance weights 215.

The mechanism thus described furnishes the normal feed increment to compensate for wheel wear and truing, the extent of which is determined by the setting of the screws 2'" and 212. An additional feed increment, the amount of which is dependent on the gage response, is superposed thereon, and determines the initial setting from which the normal tool feed takes place. As shown in Figures 1'? to 20, the gaging is effected by a combined gage and work loading and unloading member indicated generally at 300. This gage comprises a sleeve (see Figure 19) having an end portion of reduced external diameter as at 30!, this diameter being such that it may enter an unground work piece W, as shown in Figure 20. Back of this reduced diameter portion is a larger diameter portion 302 which may enter within a ground work piece W, as shown in Figure 19. The outer end portion of the sleeve 300 is provided at one side with a slot 303 in which rides one end portion of a gaging lever 304 provided at its outer end with a hardened gaging abutment 305 which is adapted to directly engage the inner face of work piece W being gaged where it is held as by a spring 306. The fulcrum of the lever 304, as shown, is formed by a leaf spring 301 which is held rigidly at one end between the jaws 308 carried by the shank portion 309 of the gaging element and at the other clamped between portions 3|0 of the arm 304. A stop screw 3 defines the limit to which the lever 304 may be moved by the action of the spring 306. l

The rear end of the lever 304 extends between the .cores 3l2 of inductance coils 3I3, the swinging of the end of the lever between these cores affecting the reluctances of the coils to the passage of alternating current therethrough and throwing them into or out of balance with each other, depending on the position of this lever. In order that the gaging lever may be out of operation, except when a Work piece W is in gaging position, a normally open switch is shown at 3l5 having a fixed arm 3l6 and a spring arm 3!! which may be pushed into contact with the fixed arm by means of a plunger 3l8 normally spring pressed into switch-open position as by the spring 3l9 reacting between a bearing shoulder 320 through which the plunger 3! is slidable, and a collar 32! secured to the plunger. The forward end of the plunger extends through a bearing 322 and when no work piece is in position extends forwardly thereof as shown in Figure 20, but when a work piece W to be gaged is in gaging position, this plunger 3l8 is pressed rearwardly thereby and the switch 315 is closed as shown in Figure 19. This gaging and work presenting and withdrawing element is shown as secured to an arm 325 carried by a carriage 326 guided for rectilinear motion in the machine frame and caused to be traversed by fluid pressure which is admitted or discharged by suitable valve mechanism (not shown), but which may be controlled by a cam on the cam shaft 235, from opposite ends of a cylinder 333 on either side of the piston 334, the rod 335 of which is operatively connected to the carriage 326 and the arm 325.

Work pieces to be ground are delivered to a chute 340 (see Figures 17 and 18) and descend to the lower portion thereof where there is positioned a pair of pins 34l and 342 which alternately project and are retracted from the path of motion of the work pieces, as by the rocking motion of an arm 344 carried by a rock shaft 345 and having slots at its ends into which are engaged cross pins from the pins MI and 342. The lever arm 344 is rocked by a lever 346 which may be struck by a pin 34'! projecting laterally from the arm 325 on retraction of the gage member from the work holder, thus to project pin 34 I,

into stopping relation to the next to the end work piece in the chute 340 and to retract the pin' 342 to free the lowest work piece to pass into position where the gaging element may engage in it as shown in Figure 20, and by which it may be thrust forward into the work holder. When the gaging element moves forwardly to present an.

unground work piece to the work holder, the pin 34! is moved away from the arm 346 which returns by gravity to the position of Figure 17, retracting the pin 34! and projecting the pin 342. This allows the column of work pieces to descend, the lower piece being stopped by the pin 342.

On retraction of the gaging piece after a gaging operation and while it is withdrawing a work piece W' therewith, this work piece-is engaged r by the forward ends of spring fingers 348 which prevent its retraction with the gaging head, releasing it therefrom so that it is discharged from the machine as through the chute 350. Thus at each forward motion of the gage toward the work holder it first picks off a piece of work from the supply chute and presents it to the work holder which is closed upon it. It then withdraws a portion of its distance, and the machine indexes, bringing a completed piece of work into alinement therewith. The gaging head is then pushed forward further than previously so as to bring the work piece W into gag ing position as shown in Figure 19, and then as it fully withdraws, the gaged and finished work piece is removed from the gaging head and escapes through the chute 350, the gaging head being then in position to receive a fresh work piece on its next forward motion to present it to the work holder from which the finished piece has been withdrawn.

Figure 26 illustrates diagrammatically the gaging circuits by which a gaging response to the size of the work is produced and a compensating feed of the finishing grinding wheel is produced in a direction to cure any deficiency in the feed of the wheel for the succeeding grinding operation determined by gaging the previously ground piece of work. Referring to this diagram, electric power may be supplied from a suitable alternating current source through the lines 400 and 4M to the primary of a transformer 402, and if necessary, through a suitable voltage regulator shown diagrammatically at 403. From the secondary of the transformer 432 power is taken through the line 404 to the differential transformer 405 having the windings 408 and 431. These windings 406 and 403 are arranged in a bridge circuit with the two coils 3l3 of the gaging mechanism. Thus one end of the coil 406 is connected through the lines 403, 409 and em to one of the coils 3E3, the opposite end oi this coil being connected to the other coil 3l3 and through the lines 4 and 412 to the transformer coil 431. Midway between the coils 3i3 there is a connection through the line M5 to the mid-point of a slider 416 oi a potentiometer 46?, one side of which is connected to the line 409 and the other side oi which is connected through the line did back to the secondary of the transformer 492. This potentiometer provides for a magnification adjustment of the gaging response. Also connected into the lines 4!! and M2 is a variable resistance 42!] the opposite end of which is connected through the line 42E to the line 409. A slider 622 on this resistance is connected through theline 423 to the common point 425 of the transformer coils 405 and 401. Variations of the setting of this slider 422 eflect the balance or amount of lack of balance of the bridge circuit and constitute the corrective follow-up. The extent or any unbalance is shown by the position of the pointer of the microammeter 425 which is supplied with rectified current from across the bridge circuit through the lines 408 and 426 and a full wave rectifier at 421. This line 426 is connected into the line M2.

A low voltage supply of any suitable description is led into the system through the leads 430 and 43L The lead 43! connects through the lead 432 to the pointer 433 of the microammeter, and when this microammeter is out of balance as shown, this needle may make contact at 43c through the lead 435 with one side of a switcn 436. When this switch 436 is closed, it makes a connection through the lead 431 through a relay coil 438 with the opposite side of the supply line 430, this coil when energized serving to close and maintain closed the switch 435 and also a switch 440. The switch 440 when closed establishes a connection from the lead 433 and the lead 4 through the relay coil 444, the line 445, to the movable switch contact 3H in the gaging head, and when the work is in gaging position closing the switch contact, connects through the line 446 back to the opposite side of, the supply line 43I. The energization of the relay coil 444 closes the switch arms 450 and 45l and establishes a connection from the high voltage lines 452 and 453 to a solenoid 454 in which extends a core 455 of a fluid pressure valve 456, so that when this coil 454 is energized the core 455 is drawn thereinto, opening up a fluid pressure passage 45'! past the valve head 458, the pipe 459 and beneath the piston 460 in a fluid pressure cylinder 46I, causing the raising of this piston. The rod 462 of this piston 460 engages an arm 463 secured to the shaft 258 (see Figures 15, 16 and 26) and turns this shaft 258 to an extent greater than that imparted thereto by the compensating cam 263, while at the same time it moves the slider 422 along the resistance 420, changing the conditions or balance or unbalance oi the bridge circuit and thus changing the direct current supplied to the ammeter 425. On balance being reached, taking into account the comparative reactances of the coils 313 (depending on the gaging position of the lever 304, which in turn is controlled by the size 01' the work being gaged), the contact between the needle 433 and the line 435 is interrupted, opening the circuit through the relay 438, which in turn opens the circuit through the switches 450 and 45! and stopsthe pull of the solenoid 454. Thereupon a spring 410 returns the valve stem 456 to the position shown in Figure 26 wherein the pipe 459 is open to the discharge pipe 41 l, and fluid pressure from pipe 451 passing through the pipe 412 above the piston 460 acts to return this piston to its lowered position. This allows the parts, including the corrective follow-up resistance slide 322, to return to their former positions, but as the arm 463 has already been lifted and the additional feed of the wheel produced, the desired results have been accomplished. It will be noted that the fluid pressure supply leads to both sides of the piston 460 but due to the greater area beneath the piston than above it, the piston rises wsh en the valve 466 admits pressure to the pipe 5 c.

Since it is important that no feed compensation shall be produced when the parts are thus returned to their former position, provision is made by which this is prevented. This is done by the action of a cam 415 secured to the cam shaft 235 by which the various controls of the machine are produced, this cam having a cam projection 416 thereon, which, when compensation is desired, is arranged to close the switch at 411. This switch is in the circuit from the low voltage lines 43l to the line 480. At all other times this switch 411 is open and until it is closed the solenoid 438 cannot be energized to close the switches 44B and 436. It will be evident that where the bridge circuit is subjected to alternating current voltage various forms of variable impedance can be employed for the electrical characteristics compared, as, for example, variable resistances, inductances or capacitances, as may be found convenient.

As a matter of convenience the term untooled wor has been used herein to denote the work piece to be operated upon and sized by the machine, and the work piece after the machine has operated thereon and brought up to a desired dimension has been termed tooled work, but it should be understood that these are relative terms only, as machining and tooling operations would commonly be performed on the work piece prior to the sizing operation.

From the foregoing description of certain embodiments 01 this invention, it will be evident to those skilled in the art that the invention may be embodied in other types of machines and with many modifications without departing from the spirit or scope of this invention as defined by the appended claims.

I claim:

1. A sizing machine having a sizing gage, means responsive to work size when tested by said gage, means producing a standard sizing response, means for supporting work, means for supporting a tool for operation on work on said work supporting means, means for relatively moving said supports to determine the completed size of work subjected to the tooling operation, and means controlled by diflerences in response of said two responsive means actuating said moving means in a manner to minimize such differences.

2. A sizing machine having a sizing gage, means responsive to variations of work size when tested by said gage, means for supporting work, means for supporting a tool for operating on work on said work supporting means, means for relatively moving said supports to determine the completed size of work subjected to the tooling operation, means controlled by said responsive means at the end of a sizing operation determining the relative positions of said supports in proportionality to such size variationsas produced by said moving means for a subsequent sizing operation, and means rendering said responsive means inoperative to effect said controlling means except when a work piece is in position to be tested by said gage.

3. A sizing machine having a sizing gage, means responsive to work size when tested by said gage, means producing a standard sizing response, means for supporting work, means for supporting a tool for operation on work on said work supporting means, means for relatively moving said supports to determine the completed size of work subjected to the tooling operation, means controlled by differences in response of said two responsive means actuating said moving means in a manner to minimize such difierences, and means rendering said responsive means inoperative to effect said controlling means except when a work piece is in position to be tested by said gage.

4. A sizing machine having a work support, a tool for operating on work held by said support, means for feeding said tool with respect to the work, a work gage for a work piece and giving a response to work gaged thereby proportional to a dimension of said work piece, means producing a standard response corresponding to the desired dimension, and means responsive to the difference between said gage response and said standard response for adjusting said feeding means.

5. A sizing machine having a work support, a tool for operating on work held by said support, means for feeding said tool with respect to the work, a work gage for a work piece and giving a response to work gaged thereby proportional to a dimension of said work piece, means producing a standard response corresponding to the desired dimension, means responsive to the difference between said gage response and said standard response for adjusting said feeding means, and means for rendering said responsive means inoperative in the absence of a work piece in gaging relation to said gage.

6. A sizing machine having a work support, a tool for operating on work held by said support, means for feeding said tool with respect to said work support during the sizing operation by a definite amount from a starting position for each work piece,.means for automatically gaging the work while it is held by said support at the conclusion of a sizing operation, and means controlled by the response of said gaging means for setting said feeding means to the starting position for the next sizing operation by an amount proportional to the departureof the work gaged from the desired gaged dimension.

'7. A sizing machine having a work support, a tool for operating on work .held by said support, means for feeding said tool with respect to said work support, means for removing the work after a sizing operation from said support and for supplying unsized work to said support, said removing and supplying means including a gaging means for gaging the sized work before it is removed, and means controlled by the response of said gaging means to the sized work for adjusting said feeding means.

8. A sizing machine having'a work support, a tool for operating on work held by said sup- 'port, .means for feeding saidtool with respect work-gaging means during such gaging for con-' trolling the limit of such feeding means for the next subsequent sizing operation.

9. A sizing machine having a work support, a tool for operating on work held by said support, means for feeding said tool with respect to said work support, work-gaging means, means for automatically actuating said feeding means to feed said 'tool toward the work during the sizing operation and to then retract said tool from the work and to efiect a gaging action of said work-gaging means, and means responsive to said work-gaging means during said gaging action for actuating said feeding means and controlling the limit of feed of said feeding means for the next subsequent sizing operation.

10. In an internal grinding machine having a work support, a grinding wheel for operating in a hole in work carried by said support, and means for feeding said wheel relative to the work during the grinding of each work piece, a gage for measuring the size of hole in a ground work piece, and means controlled by the response of said gage to a gaging operation to determine control of said feeding means for a subsequent grinding operation. I

11. In an internal grinding machine having a work support, a grinding wheel for operating in a hole in work carried by said support, and means for feeding said wheel relative to the work during the grinding of each work piece, a gage over which a ground work piece may be engaged, means responsive to the gaging response of said gage to such work piece for adjusting the retracted position of said feeding means for the next subsequent grinding operation, and means for actuating saidfeeding means a predetere mined amount from said adjusted retracted position for said next grinding operation .to cause said gaging action to determine the setting of the wheel for determining the final size of the next work piece ground.

12. A sizing machine having a work support, a tool for operating on work held by said support, means for feeding said tool with respect to work held by said support, a gage for measuring sized work having an electrical characteristic variable in accordance with a dimension of the WOI'K gaged, a bridge circuit containing said gage and responsive in its condition of balance or lack of'balance to the value of said characteristic, means responsive to said condition controlling a setting of said feeding means, and corrective follow-up means actuated by the control of said feeding means to bring said condition to a predetermined state.

13. A sizing machine having a work support, a tool for operating on work held by said support, means for feeding said tool with respect to work held by said support, means for producing a corrective action on said feeding, means, means for gaging a. sized work piece, means responsive to a departure in the response of said gaging means during a gaging action from a response corresponding to the desired dimension for actuating said corrective means, a corrective follow-up for said responsive means interposing a response equal to said departure when said correcting means has been adjusted to proper correction, and means then acting out of control of said gage for setting said followup to initial condition for a subsequent gaging operation.

14. A multiple spindle machine having a plurality of work holders and a plurality of tool holders with which work pieces on said work holders cooperate successively, one of saidtool holders having a tool for providing the final sizing machining operation for work carried by all of said work holders, means producing a tool feed of predetermined amplitude for said final sizing tool from an adjustable starting position; means for gaging a work piece after said final sizing operation has been performed thereon, and means responsive to departures from the desired size of the work piece so gaged to adjust said starting position for a subsequent sizing operation to reduce the amount of such departure in the sizing of the work piece to be sized in said subsequent operation.

15. In a machine of the class described having a work support, a tool support and means for feeding said tool support relative to said work support, a gage with which tooled work may be measured, mechanism associated with said feeding means comprising a pair of rotary elements, means for continuously driving said rotary elements in opposite directions, an element shiftable into driven relation to either of said rotary elements and having an intermediate neutral position out of driven relation with both of said elements, means in clutching relation with said shiftable element when said shiftable element is in driven relation to one only of said rotary elements for driving said feed means, means actuated by a departure in response of said gage to a response indicating correct work size for shifting said shiftable element into driven relation to said one rotary element to thereby effect actuation of said feeding means in size-correcting direction, a corrective follow-up actuated by rotation of said shiftable element in either direction for overcoming the effect of said response departure after a predetermined extent of corrective actuation of said feeding means, means acting on the overcoming of said effect to shift said shiftable element into driven relation to said other rotary element, and thereby efiect return of said corrective follow-up to its initial position, means actuated by such return to shift said shiftable element to its neutral position, and means for holding said gage inoperative except when a work piece is in gaging relation thereto.

16. A combined work supporting member and gage having a pair of work-engaging parts of diiferent size, the size of one part being that for supporting untooled work and the size of the other part for supporting tooled work, means cooperating with said other part only for gaging a tooled dimension of work positioned thereon, and means for moving said supporting member while supporting work to transfer the work supported thereby from one to another position.

17. A combined work supporting member and gage for internal work comprising a plug having an end portion of smaller external diameter arranged to be inserted in untooled work and a portion of larger diameter for insertion in tooled work and of too large diameter to receive untooled work, means cooperating with said larger diameter portion only for gaging the internal diameter of workvpositioned thereon, and means for moving said supporting member while supporting work to place untooled work engaged thereby into tooling position and to remove tooled work from said position.

18. A combined work supporting member and gage having a pair of work-engaging parts of difl'erent size, the size of one part being that for supporting untooled work and the size of the other part for supporting tooled work, means cooperating with said other part only for gaging a tooled dimension of work supported thereon, and means rendering said gaging means inoperative to produce a gaging response except when a work piece is in gaging relation to said other part.

19. A combined work supporting member and gage for internal work comprising a plug having an end portion of smaller external diameter arranged to be inserted in untooled work and a portion of larger diameter for insertion in tooled work and of too large diameter to receive untooled work, means cooperating with said larger diameter portion only for gaging the internal diameter of work thereon, and means rendering said gaging means inoperative to produce a gaging response except when a work piece is in gaging relation to said larger diameter portion.

20. The combination with a plug having a portion of smaller diameter for insertion into untooled work, and a portion of larger diameter for insertion into tooled work and of too large di-- ameter for insertion into untooled work, a work feeler positioned to engage the inner face of work on said larger diameter portion, gaging means responsive to the position of said feeler, and means for moving said supporting member while supporting work to transfer work from one to another position.

21. The combination with a plug having a portion of smaller diameter for insertion into untooled work, and a portion of larger diameter for insertion into tooled work and of too large diameter for insertion into untooled work, a work feeler positioned to engage work on said larger diameter portion, gaging means responsive to the position of said feeler, and means for rendering said responsive means inoperative except when a work piece is positioned on said larger diameter portion.

22. A work loading and unloading member having a pair of work eng ing P rts of different sizes, the size of one of said parts being that for cooperation with untooled work and the size of the other part that for cooperation with tooled work, means for moving said member to deliver untooled work engaging said one part to tooling mechanism and to remove tooled work engaging said other part from said mechanism, and means associated with said other part for gaging a dimension of tooled work received from said mechanism.

23. In combination, a work loading and unloading member comprising a plug having a portion of smaller diameter for entering an untooled hole in the work, and a larger diameter portion for entering the tooled hole in similar work and of too large diameter to enter the untooled hole, means for moving said member to engage in the untooled work and present said work to tooling mechanism and toengage in the hole 01' tooled work at said mechanism and unload the tooled work therefrom, and gage mechanism comgagement within 'the tooled hole of work on said larger diameter plug portion.

24. In combination, a work loading and unloading member comprising a plug having a por- I tion of smaller diameter for entering an untooled hole in the work, and a larger diameter portionfor entering the tooled hole in similar work and of too large diameter to enter the untooled hole, means for moving said member to engage in the untooled work and present said work to tooling mechanism and to engage in the hole of tooled work at said mechanism and unload the tooled work therefrom, a gage mechanism comprising a feeler carried. by said member for engagement within the tooled hole of work on said larger diameter plug portion and means responsive to the position of said feeler, and means for rendering said responsive means inoperative in the absence of work from such larger diameter plug portion.

25. A sizing machine having an internal sizing gage, means responsive to work size when tested by said gage, means for effecting successive inside tooling operations on work pieces, means automatically testing each piece of work by said gage after the tooling operation for that piece and before the commencement of the next tooling operation, and means controlled by said responsive means, when such test is made, effective on said efiecting means for the next subsequent tooling operation and proportional to the extent of departure of the interior of the work tested from the desired size to reduce the departure from the desired size of the next tooled work piece.

26. A sizing machine having a work support, a

tool for operating on work held by said support, means for relatively moving said tool and work on said supportdu'ring a sizing operation to produce sizing tooling operations on the work.-a work gage, means for presenting said gage to the work on said work support after the tooling operation has been performed thereon, and means controlled by the response of said gage to a completed workpiece to adjust said relative moving means for the next succeeding sizing operation in accordance with and proportional to departure from a desired dimension of a completed workpiece.

2'7. In a machine of the class described, a work support, a tool for operating in a hole in work carried by said support, and means for feeding said tool relative to, the work, a plug having a smaller dimensioned portion for insertion into the hole of untooled work, and a portion of larger dimension for insertion into the hole of tooled work, means for actuating said feeding means to engage said smaller dimensioned portion in the hole in untooled work and to deliver said un= tooled work to said work support and to engage said larger dimensioned portion in tooled work on said support andremove said tooled work from said support, gaging means associated with said larger dimensioned portion for gaging the tooled work, and means responsive to said gaging means for controlling a relation between said work support and said tool.

28. In an internal grindingfmachine having a work support, a grinding wheel for operating in a hole in work carried by said support, means for feeding said wheel relative to the work a predetermined amount for each grinding cycle, means for effecting traverse between the wheel and work and to remove the wheel from the work at the end of a grinding operation, means for gaging the work while said wheel is removed from the work, and means responsive to said gaging means during a gaging operation to adjust the starting feed position of said wheel in advance of the next grinding operation.

rmaron a. 

